xml/dom-openapi/src/com/intellij/util/xml/Converter.java

   1 /*
   2  * Copyright 2000-2009 JetBrains s.r.o.
   3  *
   4  * Licensed under the Apache License, Version 2.0 (the "License");
   5  * you may not use this file except in compliance with the License.
   6  * You may obtain a copy of the License at
   7  *
   8  * http://www.apache.org/licenses/LICENSE-2.0
   9  *
  10  * Unless required by applicable law or agreed to in writing, software
  11  * distributed under the License is distributed on an "AS IS" BASIS,
  12  * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
  13  * See the License for the specific language governing permissions and
  14  * limitations under the License.
  15  */
  16 package com.intellij.util.xml;
  17
  18 import com.intellij.codeInsight.CodeInsightBundle;
  19 import com.intellij.ide.IdeBundle;
  20 import org.jetbrains.annotations.NonNls;
  21 import org.jetbrains.annotations.Nullable;
  22
  23 /**
  24  * Base DOM class to convert objects of a definite type into {@link String} and back. Most often used with
  25  * {@link com.intellij.util.xml.Convert} annotation with methods returning {@link com.intellij.util.xml.GenericDomValue}&lt;T&gt;.
  26  *
  27  * @see com.intellij.util.xml.ResolvingConverter
  28  * @see com.intellij.util.xml.CustomReferenceConverter
  29  *
  30  * @param <T> Type to convert from/to.
  31  *
  32  * @author peter
  33  */
  34 public abstract class Converter<T> {
  35   @Nullable
  36   public abstract T fromString(@Nullable @NonNls String s, final ConvertContext context);
  37   @Nullable
  38   public abstract String toString(@Nullable T t, final ConvertContext context);
  39
  40   /**
  41    * @param s string value that couldn't be resolved
  42    * @param context context
  43    * @return error message used to highlight the errors somewhere in the UI, most often - like unresolved references in XML
  44    */
  45   @Nullable
  46   public String getErrorMessage(@Nullable String s, final ConvertContext context) {
  47     return CodeInsightBundle.message("error.cannot.convert.default.message", s);
  48   }
  49
  50
  51   /**
  52    * @deprecated {@link com.intellij.util.xml.converters.values.NumberValueConverter}
  53    */
  54   @Deprecated
  55   public static final Converter<Integer> INTEGER_CONVERTER = new Converter<Integer>() {
  56     public Integer fromString(final String s, final ConvertContext context) {
  57       if (s == null) return null;
  58       try {
  59         return Integer.decode(s);
  60       }
  61       catch (Exception e) {
  62         return null;
  63       }
  64     }
  65
  66     public String toString(final Integer t, final ConvertContext context) {
  67       return t == null? null: t.toString();
  68     }
  69
  70     public String getErrorMessage(final String s, final ConvertContext context) {
  71       return IdeBundle.message("value.should.be.integer");
  72     }
  73   };
  74
  75   @Deprecated
  76   public static final Converter<String> EMPTY_CONVERTER = new Converter<String>() {
  77     public String fromString(final String s, final ConvertContext context) {
  78       return s;
  79     }
  80
  81     public String toString(final String t, final ConvertContext context) {
  82       return t;
  83     }
  84
  85   };
  86
  87 }